Apparatus for imparting stretchability to webs



Jan. 3, 1939. I v w. w. ROWE El Al. 0

APPARATUS FOR IMPARTING STRETCHABILITY TO WEBS Original Filed July 15, 1952 6 Sheets-Sheet 1 NVEN flaw M 422 Jan. 1939- w. w. ROWE ET AL Re. 20,970

APPARATUS FOR IMPARTING STRETCHABILITY T0 WEBS Original Filed July 15, 1932 6 Sheets-Sheet 2 m i g Q Mm Mil Jan. 3, 1939.

w. w. ROWE ET AL Re. 20,970

APPARATUS FDR IMPARTING STRETCHABILITY TO WEBS Original Filed July 15, 1932 6 Sheets-Sheet 3 v nil INV?TORS ATTORNEYS Jan. 3, 1939. w, w, ROWE ET AL Re. 20,970

APPARATUS FOR IMPARTING STRETCHABILITY 'IO WEBS Original Filed July 15, 1932 6 Sheets-Sheet 4 ATTORNEY;

Jan. 3, 1939. w. w. ROWE El AL 20,970

APPARATUS FOR IMPARTING STRETCHABILITY T0 WEBS Original Filed July 15, 1932 6 Sheets-Sheet 5 ATTORNEYi Jan. 3, 1939. Re. 20,970

APPARATUS FOR IMPARTING STRETCHABILITY TO WEBS w. w. qwragsr AL Original Filed July 15, 1952 6 Sheets-Shae}, 6

msmi'ros ron msn'rmo s'ma'ron- ABILITY TO WEBS' I William Wallace Rowe, Cincinnati, and Warren A. Morris, Wyoming, Ohio, assignors to The Paper Service Company, Loekland, Ohio, a corporation oi Ohio Original No. 2,034,421,. dated March 17, 1930, Se-

rial No. 622,698, July 15, 1932. Application for reissue Mme 1a, was, Serial No. 196,304

28 Claims. (crass-so) Our process and. apparatus relate to the pro duction of corrugations or other configurations in paper 9:, other webs, whereby the web is rendered stretchable transversely of the" said configurations. While applicable to single pieces or sheets, our invention is of particular importance inthe treatment of continuous webs. As such, it is directed to the continuous production of configurations longitudinally of the web. Hence it is one of our obiects to provide a method and means for corrugating a web longitudinally so as to impart widthwise stretchability thereto.

Our invention is applicable either to plain webs,

or to webs which have been creped prior to our treatment or will-be creped thereafter. so that our invention provides a method and means for imparting the qualtity of multi-lateral stretchability to webs. Multi-lateral stretchability may also be produced-in accordance with our invention by giving two treatments to the web, the secnd at an angle to the first.

It has hitherto been proposed to corrugate paper longitudinally by passing it between corrugated rolls, or by pulling it through a device comprising fiuted plates. The difilculty presented by the first proposal is to be found in the fact that the formation of longitudinal corrugations implies a widthwise contraction, which the rolls do not properly permit. The second proposal faces the dlfllculty of pulling the paper through a forming device, with the attendant danger of breaking it. Moreover, the second proposal is not applicable to webs which have previously been given a longitudinal stretchability by being transversely creped or corrugated, since thepull on the paper will of necessity remove a great part, if not all of the stretch therein.

We shall describe our invention herein in connection with the treatment of a previously creped web of paper, since this presents the greatest number of problems, it being understood however, that this is not a limitation upon our invention. Generically our invention contemplates forming means which travel with the sheet, the sheet being engaged, at the same time, by means, traveling with it or not .as desired, which assist in forming it to desired configurations. Broadiy stated, our invention comprises (1) means which, whether integral or discrete, present a series of rugosities or interspaced contacting elements for the sheet initially, 2) means fordisplacing the sheet between or with reference'to the said rugositi'es, or interspaced contacting elements, and

(3) means for maintainingthe said displacement of other portions, or

oi portions of the web during the displacement I means for preventing the loss of previously formed displacements during the. augmentation'of said' displacements. This means may also comprise means for preventing the re-expansion of the sheet as by crushing or setting the corrugations, or the like. Means for performing the three functions ,hereinabove set forth are generic to our invention, although in some specific embodiments certain of the functions are performed, in part at least, by means in common.

Examples of the first means are, by way of illustration, a table-like member or plate of metal or. other material, a belt, etc., the surface of which is provided with corrugations or rugmities extending in the general direction of sheet travel; a composite support or surface formed of discrete elements such as traveling belts, chain elements or the like; a grooved cylinder, etc.

The second means may vary with respect to the first. Examples of the second means not only include any mechanical or fluid agency for depressing the paper between the rugosities of the first means, but also mechanical means for gripping the web in conjunction with the first means, where the displacement is caused by a movement of the first and second means, or otherwise. The second means may, by way of illustration, comprise a series of interspaced belts, bands, rollers, or conveyor-like elements. In our invention either the first or the second means (and in our preferred types of organization, both) will move with the sheet or web being treated, whereby the strain on theweb is diminished and certain other vention there are certain specific modifications.

It will be remembered thatif a sheet or web is corrugated or given other configurations longitudinally', there will be awidthwise contraction therein. If deformations are attempted to be made entirel across the width of the sheet at one time by inter-digitating members difllcuity will be. had because the contraction is cumulative,

' because the edges must take up relatively ,more' than the center-portions, and because the sheet will-not slip'rea'dil'y with respect to the mechanical agencies engaging it across itsface, so as to aspect of our invention we avoid'this dimculty by causing the second means hereinabove dethese latter belts may be caused to depress the web between the corrugations of the first means successively in the direction of travel of the web. To make this more specific, in one aspect of our invention we bring down a central belt first and cause it to make, in co-operatlon with the first mentioned means, a central groove or corrugation in the web, then at interspaced points in the travel of the web we successively bring down pairs of belts into forming position, one on either side of the center line of the sheet. This may be referred to as the successive interengagement of members.

In a second modification of our invention we cause the members inter-engaging the sheet to converge progressively and/or successively in the direction of travel of the sheet or web so that the web is contracted widthwise by the convergence of these members. Where the members merely grip the sheet at interspaced points or linesand then converge as aforesaid, the slack in the sheet forms itself into corrugations, or other configurations between the interspaced members. Where the members come into inter-digitating relationship they may be caused to do this simultaneously across the width of the sheet, but progressively in the direction of its travel so that the convergence aforesaid provides sumcient slack for the complete interengagement of the members without rupturing the sheet; Both species provide means of obtaining cumulative contraction wldthwise, in that the edge portions of the sheet are contracted cumulatively more than the portions near the center.

Modifications may be made in these species, I

and of course they may be combined as by first corrugating the sheet by the successive interengagement of forming members and then making the corrugations deeper by causing the members still traveling with the sheet to converge in the direction of travel. Still other modifications may have progressive convergence combined with progressive interengagement.

As will be pointed out hereinafter, it is necessary when corrugating highly flexible webs, such as paper or the like, to provide means for maintaining corrugations already formed therein while forming additional ones, or while modifying the shape of the corrugations.

Finally it will usually be the practice to crush or otherwise set the corrugations as by drying,

'cooling, cementing, or the like. This may be done after the complete formation thereof, or the corrugations may be crushed as they are formed.

The objects of our invention which will be apparent from the foregoing or will be clear to those skilled in the art upon reading these speciflcations, we accomplish by that process and mechanism of which we shall now describe certain exemplary embodiments, reference being bad to the drawings which form a part hereof.

In the drawings:

Figure 1 15a plan view, and Fig. 2 an elevation of a mechanism in which the members enaccommodate the contraction aforesaid. In one gaging the sheetare caused to converge prograsively in the direction of the travel of the sheet.

Figs. 3 and 4 are respectively partial sectional views taken'along the lines I, 8 and l, l of Fig. 2.

Fig. 5 is an elevational view of a device employing successive interengagement, the first means hereinabove mentioned being a grooved cylinder. a

Fig-6 is a view of a device ior causing and maintaining the interengagement of members in the first and second means.

Fig. '7 is a front elevation of the device of Fig. 5. Fig. 8 is a semi-sectional view of the device of Fig. 5, taken along the lines 8, I.

Fig. 9 is a plan view, and Fig. 10 an elevation of a type of device employing successive interengagement in connection with a plate as the first mentioned means.

Fig. 11 is a sectional view taken along the lines li,ilinFig. 10.

Fig. 12 is a type of device employing successive interengagement where the means first mentioned hereinabove is a series of belts. I

Fig. 13 illustrates in plan and Fig. 14 in elevation a device employing both successive interengagement and converging of the members in the direction of travel thereof.

Figs. 15-20, inclusive, are semi-diagrammatic illustrations of the deformation of a web by successive interengagement of the forming means. The conditions illustrated by these figures are produced in the machines of Figs. 5, 9, 10, 12, 13

, and 14.

Fig. 21 illustrates in elevation a device employing gripping members which converge in the didevice The figures are semi-diagrammatic in theirnamay be made in the specific mechanism employed tion. a

In Figs; 1 to 4, inclusive, there is illustrated a type of machinein which there are members which come into interengagement and also converge as they travel with the sheet. We have shown a lower series of belts l and an upper series I. The lower series passes over interspaced rolls or sheaves 5 and 8, which will preferably be driven, and which are grooved to receive the belts. The upper series passes over interspaced rolls or sheaves I and 9 which will likewise be grooved, and may be driven. It will be noticed that the belts and hence the grooves are further-apart on rolls I and 5 than on 8 and 9. The belts -there-' fore converge in the direction of travel as they engage the sheet Ill, and diverge again as they return over the rolls, out of contact with the web. Should there be any difilculty in maintaining the direction of travel of the belts, suitable guiding forming elements, yet they need not be discrete ture and it will be understood that modifications members. The belts may be interconnected mechanically i1, desired, or may be parts of one traveling member, such as a belt of rubber or the like, in which the progressive convergence and divergence are taken care of by contraction or expansion of the rubber between the forming elements.

In the embodiment of Figs. 1 to 4, the series of belts I and 2 may be regarded indiscriminately as the first or second means hereinabove referred .to, it being understood that the functions of both are present.

The rolls 5 and i are further apart than the rolls 6 and 9, and it is our object to produce a progressive interengagement of the belts as they converge, which interengagement is, however, simultaneous across the width of the sheet. Devices are provided to bring the belts into interengagement and to hold them there. As an exemplary showing, we have disclosed a series of rolls l3, ll,

' l5, l6 etc. which may be staggered on either side of the belts. These rolls may be spring mounted, and may be so adjusted as to make the inter'engagement of, the belts proportionate to the convergence thereof. They may also be employed in opposed pairs, or other holding and controlling means may be substituted for the rolls, as bars, plates, conveyor elements, etc.

Fig. 3 shows the traveling elements as they begin to interengage; Fig. 4 shows how, after complete interengagement slack may be formed widthwise of the web by a further convergence of the belts.

It will be obvious that with a modification of the devices l3 to H, inclusive, other means may be substituted for the lower or upper series of belts I or 2, such as a smooth, straight or curved plate having converging grooves cut therein. So long as there is one series of forming elements such as the belts 2, moving with the web so as to propel it, the other means employed need not necessarily move providing there is no great frictional engagement between the web and means not traveling therewith. We prefer of course, to have both sets of means traveling with the web, since under these circumstances the web is subject to substantially no strains longitudinally,

whereas the widthwise strains are taken care of by means hereinabove described. It is readily possible in our process and mechanism to corrugate'relatively heavy webs, boxboards, strawboard and the like, which may or may not have been softened by a water treatment, or webs which have previously been creped and have a longitudinal stretchability which it is desired to retain. When the corrugations or other configurations have been completely formed, it is desirable to set them in the paper by crushing or otherwise, and in Figs. 1 and 2 we have shown a pair of crushing rolls l8 and I! located so as to engage the sheet just after it leaves the corrugating devices. This type of crushing mechanism is not necessary however, and in some installations we have secured excellent results by running the paper bethe thickness of the sheet, thereby making it more dimcult to pull the stretchabiiity out. the stretchability is to be removed from a sheet having crushed corrugations, the web has to increase in thickness, or else the pleats have to roll or peel. This action is further resisted where the web is confined under pressure, as when it forms the liner between the contents and the outer wall of a burlap bag or the like. Such pressure would tend to flatten out uncrushed corrugations; but it will tend to hold crushed corrugations. Similar actions occur when shee are stacked, stored or baled.

In Fig. 5 we have illustrated a type of mechanism embodying the feature of a successive interengagement of forming members as distinguished from a convergence thereof during the course of travel. The first of the essential means hereinabove referred to is in this case a cylinder 20, which is provided with parallel grooves 2i about its periphery. A web of paper, or the like, 24, which may previously have been creped by means of the cylinder 25, the back-up roll a, and the doctor 26, is led to the surface of the cylinder 20 and about the surface thereof, through as large an are as is practical. In the course of travel of the web portions of it are successively displaced into the grooves of the cylinder by means of belts, wires, or other forming elements as shown. All of these wires indicated generally at 21 pass over a common return sheave or roll 28. The central wire indicated at 21:; passes over sheaves 28, 29, and Si, the purpose of which are to carry the belts about the cylinder, but away from the periphery thereof in the path or return travel of the belts. The belts in their forward travel of course, pass about the surface of the cylinder and enter the grooves in a successive fashion. The first belt 21a passes over sheave 32, which" causes it to be led onto the surface of the cylinder 20in a substantially tangential direction. vA pressure roller or sheave 33 presses the belt 21a. down into the central groove of the cylinder 20, deforming the paper and producing a corrugation therein. The next pair of belts 21b, one .on either side of the belt 210, are led over a pair of sheaves 32a so as to approach the surface of the cylinder 20 tangentially, but at a point removed in the path of travel 01 the cylinder from the point of. engagement oithe belt 210. therewith. Similarly a pressure roll 33a is provided to press the belts 21b into the grooves of the cylinder adjacent the groove into which the first belt was depressed. Likewise belts 21c, 21d, etc. pass over respective pairs of sheaves 32b, 32c, etc. to cause them to approach the surface of the cylinder tangentially at interspaced points- Successive pairs of belts thus approach the surface of the cylinder at interspaced points about the periphery thereof, and are caused toenter the grooves. by the pressure rollers 33, 33a, 33b, etc. Some of the belts, since their path of travel does not comprise a great part of. the surface of the cylinder 20, may be returned over sheaves 29 or 30, instead of 2| (or any other sheaves interspaced about the periphery of. the cylinder, as will be well understood). The pressure devices 33, 3311, etc. may be held by springs 34 and may also be provided with stop means 35 so that while they approach the surface of the cylinder closely enough to depress (the belts into the grooves thereof, they cannot approach so closely as to pinch the paper againstthe surface of the cylinder.

As shown in Fig. 6, our pressure devices 33b ridges narrower than the grooves.

may have a portion indicated at 88, the purpose of which is to depress the approaching belt 21c into the groove 38 of the cylinder Ill. It likewise has a portion 39, the purpose of which is to hold in position the belt 2'"), which has previously been depressed into the groove 4! by h preceding pressure device. This is a necessa y precaution because if the belt 21c is depressed into the groove 38 without holding means for the belt 21b, the paper will pull up out of the groove ll, pulling the belt 211) part way with it, hence the desired widthwise contraction-of the paper will not be secured, unless belts were put under strong enough tension, which is possible but undesirable. Instead of separate pressure rollers 33 etc., rollers may beemployed in which the holding portions are broad enough to hold into their respective grooves all of the belts theretofore depressed. Under some circumstances the pressure rollers ,may be slightly grooved and the guiding sheaves 32, etc. eliminated.

As the paper leaves the surface of the cylinder Ill. the corrugations therein may be crushed by a pair of rolls 4!, 43, or otherwise as desired.

The nature of the action of the various devices is illustrated in Figs. '7 and 8, where, however, the pressure rolls have been omitted. It will be seen that the corrugation produced by the belt Ila is completely formed while the web has its outer portions entirely free, but before the belts 21b engage it. Likewise the corrugations produced by the belts 2112 are completed while the edges of the paper are free to pull inwardly and before the belts 21c contact it. In this manner pairs of corrugations are successively formed in the web while the web is free to draw in to accommodate the necessary widthwise contraction. It will also be apparent that should a cylinder 20 be chosen of insufficient diameter to permit the corrugating of as wide a web as desired, two or more of the cylinders, with co-operating mechanism, may be employed in tandem.

' It will be observed, practicularly inFig. 6, that the grooves in our cylinder 20 are wider than the ridges which divide them. This makes for a greater degree of stretchability in the flnshed web. If regular sinusoidal corrugations are formed there is a limitation upon the amount of stretchability which may be put into the web, because to deepen the corrugations implies a concomitant widening. In order to increase the stretchability we increase the depth of one set without increasing the width of the other or increase the depth of both sets without increasing the width of either. This may easily be done with a grooved cylinder or plate by making the Stretchability may still further be increased by deepening the 'grooves without widening them and providing pressure means of a type which will enter the deep grooves and depress the belts or wires ward the bottoms thereof.

In this embodiment of our invention the cylinder 20 is driven and likewise the various belts are preferably driven, which may he accomplished by means of power applied to the rolls 28 to 3!, inclusive, or any of them. It will be apparent that modifications may be made in this device while utilizing the particular mode of operation which it exemplifies. Thus for the cylinder 20 a member presenting a corrugated surface extending horizontally could be emp oyed, and this member could be a moving member traveling with the sheet or not, as desired. A device somewhat like a chain conveyor having a Figs. 9, 10 and 11 show a device in which there is a base plate 44, the surface of which is machined to present a series of longitudinal grooves.

Paper passes over this plate and is caused to assume a corrugated form by means acting to depress portions of it into the grooves aforesaid in a successive manner to allow for the widthwise contraction of the material. A number of mechanical means for performing this function may be employed, providing they travel with the sheet in the sense at least of propelling the sheet over the surface of the plate, and providing also that means are present to hold the corrugations already formed while additional corrugations are being formed. 0f the several mechanical means which may be employed, we prefer in this embodiment also to employ traveling belts since they may be caused to exert a continuous forming action on the sheet. We have shown a belt 45 passing over a sheave 46 by means of which it is depressed into a central groove 41 in the plate 44. At an interspaced point in the travel of the web 2, additional belts 45a may be brought down over a sheave 48, the central portion of which is shaped to hold the belt 45 in its groove. It will be clear that if the depressing means are themselves grooved, they will not depress the belts as far into the grooves of the plate. Under many circumstances grooves in the depressing means may be eliminated, especially where grooved guiding rolls (not shown) are also employed. Similarly other belts may be brought down in pairs to produce other corrugations in a successive manner. We have shown all of the belts passing over an end sheave or roll l8 and a supporting roll 5|]. Some of the belts addie tionally pass over another supporting roll II. There may, of course, be as many of these rolls as desired. We have shown pressure rollers 46 and 48 as controlled by springs from a support 52, and as the means whereby the belts are brought down to the plate and depressed into the grooves thereof. If it is desired to relieve the elements 46, 48, etc., of tension, additional sheaves may be employed corresponding to the sheaves 32, 32a, etc., of Fig. 5. Fig. 11 clearly illustrates the way in which the corrugations already formed are held while additional corrugations are being formed.

In the employment of grooved plates, it is possible to make these plates curved convexly so the pressure rollers, as hereinabove described, by

backing up rolls 56, 56a, etc.

90,070' Still another modification is shown in Figs. ability imparted by creping processes. We thus 21' to 23, where we have provided a seriesoi' secure a; product which isperfectly stretchable interspaced zripping elements which contact the in all directions. I I sheet and afterward are brought together width- Our product may be varied when made of Wise so as to cause the sheet to. be-deflected orcreped paper by what might be termed a herring 5 deformed therebetween. We have shown an bone efi'ect. Where, after contraction oi the upper series or belts I1 and a lower series of belts sheet by converging members, there is considerll passing respec tl velyover .-end", sheaves ll, 00. able looseness or the web between the forming lland". Opposed pair of rollers-83, 64,, etc. members as is shown in Figs. 4 and 23, it is posre shown. All 01" sheaves or rollersare sible to flatten. out the corrugationsin partwhile "I1," in proper spaced 1 retaining widthwi'se stretchability by driving 1 Y I a ting'the'sheet fastertha'n This may befdone in the device'oi-l lg. 4 U drivingthe wires'l raster than'the-wiresi; and in he organization otlllg. 23 by driving alternate the belts, 58 at jdiiiferentspeeds, 1nnee separate supporting sheaves for berequired.

and afterwards the depth of the corrugations may 25 be increased or slackness produced in the sheet by ,members engaging it which contact during the course of their travel with the sheet. In Figs. 13 and l4 we have shown a plate 69 having a series of grooves "a in the face thereof, which are parallel throughout a part of their length, but converging throughout another part. In the as may be made a part ot'or-mounted upon concessively brought down by: pressure device and veyors of chain or other suitable form, suitably into ihterengagement with the grooves.

- mounted to ride upoh'rails or the like, and havalso provide pressure rollers ll, 10a, etc-, lng guiding means to cause the'belts to converge. to hold the wires in the grooves during the con- The convergence of the belts or other gripping .vergence thereof, returni g the wires over an 40 means need not be concurrent, but may be sucend sheave ii in which the grooves are closer to- 40 cersive, from, the sides of the web inwardly together than in the sheaves 50 or ii. In 'order to ward the center. v provide a positive guide for the wires between the As the sheet enters the device or Fig. 21, it is sheaves, we may provide deflecting rollers or sripped at interspaced points between the belts guides 12 and "as shown, for changing the di- I1 and. 58. As these belts converge they i'orce rection'of wire travel during the return thereof. 45 a widthwise contraction of the sheet. The sheet We have illustrated in Figs. 15 to 20 diagramis shown partially contracted in Fig. 22, which is matically the principle of successive deformation a section taken'along the lines 22, 22 of Fig. 21. of the sheet. Although the lower forming ele- In Fig. 23 the belts areshownconverged and the ments have been indicated at 14, etc. as wires paper displaced between theminto' irregular ccn-' (p esupposing an app s m i k that figuratio'ns. These conflgurationswill, of course, in Fig. 12 it will be understood that other devices not be as symmetrical asthey would if positively may be substituted for these wires. The upper guided by "the supporting devices, say, of Fig. wires are indicated at 15, and the way in which 9; but this in general inakes'nodiflerence bethe sheet 16 is deformed by the successive intercause the object is-to produce in the sheet a widthengagement of the wires or other forming mem- 66 wise stretchability, and when the"'corrugations bers will be. apparent.

.arecrushed or otherwise set it makes no sub-' It will be understood that modifications may stantial diilerence whether the pleats are exactly be made in the mechanical agencies employed. symmetrical or not. 1 By way of example but without limitation, where .1 In1'lg.25'we have madeacomposite showing of supporting means traveling w t Sheet and 9 one for of our'produci; before and after t presenting to it a series of interspaced corrugacrushing treatmen This may be thought of as tions are provided, the depressing means may be a sheet or web which has previously'been creped a tapered blast of air, the purpose of which will in the usual mannen'and'which therefore has a be to Produce the effect m tic lly illusllli series of transversely extending creping crinkles trated n Figsinclusiveoughout all 55 ll, giving it lengthwise stretchability. It also has of these modifications however, our invention is a plurality f lengthwise corrugations gg After characterized by means traveling with the sheet crushing as shown m the p -1 of t figure. or web, and likewise by means having the three has ii-plurality of pleated formafi'ons 31 char. main functions hereinabove first discussed, al-

16 acterized byffold lines -68. The product can be though these fun t ns may be iv d ntly 70 j made. w muchfll-metchabmty desired between different elements as between modiflcawithin re isionablehmitsinthe transverse direcions. a

tion, and more particularly'it ispossible to equal Webs of paper or the like, particularly it in in the transverse stretchability produced by our softened condition, are not well adapted to hold p essamolints of'lengthwise'stretch .shapes imparted to them. This explains the 75 necessity of providing holding or maintaining means in connection with or as a part of supporting means and deforming means. In working with webs which must not be greatly tensioned, it is, as hereinabove explained, preferable to have at least one set of members, having one or more of the primary functions, traveling with the web. Ideal conditions are perhaps best obtained in the practice of our invention by providing supporting and deflecting means upon either side of the sheet which are both continuous and travel with the web, and by providing means for causing such a continuous interaction of such means as will retain corrugations previously produced. But excellent results may in many cases be secured by the use of means, some of which are not, continuous, and some of which may not move with the web. Crushing means may be caused to act successively on the web as corrugations are formed therein.

Having thus described our invention, what we claim as new and desire to secure by Patent, is:

1. In corrugating apparatus means presenting a corrugated surface adapted to move substantially in the same plane as a-web, the corrugations in. said surface beingsubstantially disposed in the direction of travel of said web, means I ,moving with the web acting to depress said :web

into the interstices 'of saidsurface, whereby pertions of the said web are contracted widthwise more than other portions, and means adapted to hold each corrugation continuously from the point of formation at least until the formation of the next succeeding corrugation.

2. In corrugating apparatus, corrugating means providing a series of longitudinal ridges continuously traveling with a web and successively acting means for said ridges, said means adapted to hold each corrugation continuously from the point of formation at least until the formation of'the next succeeding corrugation.

3. In a corrugatlng apparatus, means for presenting to a web a series of interspaced forming elements, and means moving with said web for deforming portions of said web with respect to portions supported by said elements, and means for maintaining a deformed condition of portions of said web, said means acting on said deforming means. I

4. In corrugating apparatus, corrugating means traveling with a web, said means adapted to present to said web, continuously, a surface having ridges, and means for depressing said web into said ridges, said means arranged to act successively in the direction of travel of said web, and means for continuously maintaining corrugations already formed during the formation of adjacent corrugations.

5. In corrugating apparatus, corrug'ating means adapted to present to a web, continuously, a stationary surface having ridges, and means for depressing said web into said ridges, said means arranged to act successively in the direction of travel of said web, means for retaining at least some of the formed corrugations during the formation of additional corrugations, said depressing means arranged to travel continuously with 'said web, and said retaining means arranged to act on said depressing means.

6.. In corrugating apparatus aplurality of 10D! 7 gitudinally disposed elements traveling with a web, a second series of longitudinally disposed elements traveling with said web, but arranged on the opposite side Letters depressing the web between thereof, and 7 means for bringing said elements into interdigitating relationship, said means arranged to act successively, and means for continuously holding said elements in interdigitating relationship when in contact with said web.

7. In corrugating apparatus, a circumferentiaiiy grooved cylinder adapted to turn with a web of material led thereabout, progressively acting means for depressing portions of said web into said grooves and holding at least some of said portions depressed while additional portions are being depressed into other grooves, and means adapted to travel continuously with said web on said cylinder to maintain corrugations therein.

8. In corrugating apparatus, a circumferentially grooved cylinder of relatively large diameter, a plurality of sheaves arranged about the surface of said cylinder in echelon formation,

- but out of contact with said surface, and means for passing belts respectively from said sheaves tangentially to the surface of said cylinder and into said grooves, whereby the points of engagement of said belts in said grooves will be disposed v in echelon formation.

9. Inan apparatus for corruga combination of a member presenting 'longitudi nally disposed lands or ridges to a web of paper upon one side, means disposed on the otherside of said web comprisinga series of belts adapted to move, continuously with said web, means for bringing said belts successively into interdigitating relationship with said lands, and means acting onsaid belts while in contact with said web, and at least at intervals throughout their length to maintain said interdigitating relationship.

10. In corrugating apparatus, the combination of a member adapted to present grooves or lands to a web, said grooves or lands being arcuately shaped in the direction of movement of said web, means for successively depressing portions of said web between said lands, and holding means comprising belts tensioned longitudinally about said arcuate lands to maintain the corrugations so formed.

11. In corrugating apparatus, the combination of means presenting a grooved surface to a web, means for depressing a web between the lands of said grooved surface, whereby to corrugate said web, means for maintaining the corrugations formed therein, a felt, pressure rolls, and means for bringing said felt into contact with said web after it is corrugated so as to bind the corrugations therein and so as to pass said web and said n g paper, the

felt together through said pressure rolls to crush u said corrugations. v

12. In corrugating apparatus, a plurality of elements adapted to present longitudinally to a web a series of lands or ridges, a second series of elements traveling with said web but arranged on the opposite side thereof, means for bringing said last mentioned elements successively into interdigitating relationship with said first mentioned elements, and means for maintaining the said interdigitating relationship of elements at least during the interdigitation of adjacent elements, the means acting on said elements being adjustable to control said relationship at least to a point at which one series of said elements is depressed beyond co-planar relationship with the other.

13. In corrugating apparatus, means presenting to a web alongitudinally ridged corrugatin'g surface, a series of belts arranged for conjoint travel with said web and disposed on the opposite side thereof, means for'bringing belts successively into paths of travel lying substantially between ridges of said first mentioned means, said last mentioned means comprising means for changing the direction of the paths of travel of said belts, and means for bringing said belts successively into positions substantially between said ridges at progressively greater distances from a given point, and means for maintaining the interdigitating relationship so produced at least during the interdigitation of adiacently disposed belts and ridges.

14. In corrugating apparatus, a plurality of elements presenting longitudinally disposed lands or ridges to a .web upon one side, a plurality of belts disposed on the other side of said web, means for bringing said belts successively into interdigitating relationship with said first mentioned means, and means for continuously maintaining said interdigitating relationship, said means comprising sheaves acting on said belts at least at intervals throughout the conjoint travel of said belts with said web.

15. In corrugating apparatus, a plurality of elements presenting longitudinally disposed lands or ridges to a web upon one side, a plurality of belts disposed on the other side of said web, means for bringing said belts successively into interdigitating relationship with said first mentioned means. and means for maintaining said interdigitating relationship at least during the interdigitation of adjacent elements, said means comprising sheaves acting on said belts at least at intervals in the conjoint travel of said belts with said web,

said sheaves being depressable between said lands or ridges, at least to the extent of depressing said belts below the tops of said lands or ridges.

16. In corrugating apparatus, corrugating means traveling with a web, said means adapted to present to said web, continuously, a surface having ridges, and means for depressing said web into said ridges, said means arranged to act successively in the direction of travel of said web, said depressing means comprising elements continuously moving with said web, and means for holding said depressing means in meshing relationship with said ridges from the point of formation of corrugations at least until the formation of the next succeeding corrugations.

17. In corrugating apparatus, a plurality of corrugating means longitudinally disposed and continuously traveling with the web, and a second series of longitudinally disposed corrugating means upon the opposite side of said web and arranged to travel continuously therewith, and

means for successively depressing members of one of said series between members of the other of said series so as to corrugate said web, and means for holding said elements in interdigitating relationship when in contact with said web from the point of formation of corrugations at least until the formation of the next succeeding corrugations.

18. In corrugating apparatus, a plurality of bands arranged to present a longitudinal ridged corrugating surface, said bands arranged for conjoint travel, a second series of bands arranged for conjoint travel, and means for bringing members of said second series of bands successively into paths of travel lying substantially between members of said first series, said means comprising means for changing the direction of paths of travel of bands in said second series, and means for bringing said first series of bands into successive positions to intersect said paths at progresssively greater distances from a given point, and means for holding said elements in interdigitatv 7 ing relationship when in contact with'said web during the formation of adjacent and succeeding corrugations.

19. In corrugating apparatus, a circumferentially grooved cylinder adapted to turn with a web of material led thereabout, successively acting means for .depressing portions of said web into said grooves, said means comprising belt-like members adapted to travel continuously with said web on said cylinder under sumcient tension to maintain the corrugations therein.

20. In a paper working machine a rotatable drum having a multiplicity of circular grooves formed in its periphery, a multiplicity of sheaves journaled in close proximity to said grooves and carrying cords which are caused to traverse said drum within said grooves, means for feeding paper stock between the sheaves and cords and the drum, and means for rotating said drum with the cords engaging'the paper stock and pressing it into the grooves while it is thus being advanced, and means for pressing and flattening out the corrugations thus formed in the paper stock.

21. A machine of the character set forth in claim 20 wherein there is associated with each groove a presser roll immediately following one of the sheaves and engaging the cord to positively press same into the groove without pinching the paper stock, the sheave having its periphery spaced from the drum a greater distance than the spacing of the presser roll to provide for a gradual engagement of the paper stock by the cord.

22. A machine of the character set forth in claim 20 wherein there is an intermediate sheave cooperating with an intermediate groove with pairs of sheaves following the first sheave and progressively distributed to successive grooves whereby the corrugations are progressively formed in the advancing paper stock from the center outwardly.

23. A machine of the character set forth in claim 20 wherein there is an intermediate groove with pairs of sheaves following the first sheave and progressively distributed to successive grooves whereby the corrugations are progressively formed in the advancing paper stock from the center outwardly, and with a single roll member disposed rearwardly of the sheaves and functioning as a common sheave cooperating with the other sheaves.

24. A machine of the character set forth in claim 20 comprising a plurality of non-grooved presser rolls journaled in close proximity to the periphery of the drum and engaging the cords to press them into the grooves without pinching the paper stock, there being a presser roller immediately following each of the said sheaves and the latter having their surfaces further removed from the peripheral surface of the drum than the surfaces of the presser rollers.

25. In a paper working machine means providing a multiplicity of grooves, sheave means journaled in close proximity to said grooves and carrying cords which are caused to traverse the said grooves, whereby a web fed between said cords and said grooves will be corrugated, and means for maintaining said cords within said grooves, said means comprising sheave means engaging said cords and narrow enough to pass with said cords into said grooves and between the ridges defining said grooves.

26. In corrugating means, an arcuate surface about which paper to be longitudinally corrutherein, belts adapted to travel in said grooves so as to causepaper" to conform to said grooves whereby to corrugate it, sheave means for guiding said belts to bring them to position for entry into said grooves and for returning said belts, and means for engaging said belts and pressing them into said grooves.

gated may be said surface having grooves- 

